Locomotive firebox equipment



July 14, 1942. c. A. SIEGEL LOGOMOTIVE FIREBOX EQUIPMENT Filed Aug. 12, 1957 2 Sheets-Sheet 1 -,FQEEEPEEEQMEEF ml INVE NTOR 4.

A-rroRNEYJ July 14, 1942. c. A. SIEGEL LOCOMOTIVE FIREBOX EQUIPMENT Filed Aug. 12, 1957 2 Sheets-Sheet 2 v INVENTOR a. a BY .1

v ATTORNEYS Patented July 14, 1942 LOGOMOTIVE FIREBOX EQUIPMENT Chester A. Siegel, Newark, N. J., assignor to American Arch Company, New York, N. Y., a

corporation of Delaware Application August 12, 1937, Serial No. 158,688

8 Claims.

This invention relates to locomotive firebox equipment and is of especial advantage in connection with a locomotive boiler having toward its rear end a combustion chamber adjoining the firebox, although it is to be understood that not all features of the invention are limited in their application and usefulness to a locomotive of this type.

The invention is concerned with a number of improvements relating, first, to bracing or strengthening the" structure of the firebox and of the adjoining combustion chamber, second, simplification of the refractory fire arch employed in the firebox, and third, improvement in the circulation in the water walls surrounding the firebox and combustion chamber.

With regard to the first of the three points mentioned above it should be borne in mind that because" of the pressure carried in the boiler and thus in the water Walls, the inner sheets defining the combustion chamber and the firebox must be effectively and rigidly stayed or braced. For this purpose the side sheets of the firebox are commonly provided with a multiplicity of staybolts', the crown sheet with crown stays, and the combustion chamber with combustion chamber stays. According to this invention additional bracing is: provided for the inner sheets defining both the firebox proper and the combustion chamber, by means of circulator devices which are configured and located in a novel manner to accomplish this purpose. Other factors in this connection will be'pointed out more fully hereinafter following a description of the accompanying drawings.

As noted above, the invention also has in view improvement in the refractory arch, this improvement consisting in arrangement of the circulator elements employed to afford better and more convenient support for the brick of which the arch is composed and also to provide for the use of only a few brick patterns throughout the entire arch.

Still further, improved circulation is provided especially in the water walls surrounding the combustion chamber and the circulator devices employed provide for delivery of water to the crown sheet in a plurality of zones not only over the firebox but also over the combustion chamber.

Various of the foregoing features are of importance in reducing staybolt failure particularly at the top of the firebox and combustion chamber, this being of very substantial importance for the reason that staybolt failures have in the past resulted in serious explosions, with consequent injury and extensive damage.

How the foregoing objects and advantages are attained, together with others which will occur to those skilled in the art will be more apparent from the following description referring to the accompanying drawings, in which- Figure 1 is a vertical longitudinal sectional view through the rear end portion of a locomotive boiler and firebox, with the improvements of this invention applied thereto;

Figure 2 is a transverse sectional view taken through the firebox substantially on the line 2- of Figure l;

Figure 3 is a transverse sectional view taken through the combustion chamber substantially on the line 3-3 of Figure 1; and V Figure 4 is a view similar to Figure l illustrating a modified form of construction.

Referring first tothe embodiment of Figures 1 to 3 inclusive, the outer boiler shell is indicated at 5, this shell being joined at its rear edge with outer sheets surrounding the firebox including the outer top sheet 6 and the outer throat sheet l. The top or wrapper sheet 6 is curved downwardly at the sides and has substantially fiat portion-s 2i'--8 at opposite sides of the firebox joined with the mud ring 9 which surrounds the lower edge of the firebox. The sheet It) completes the closure at the rear end.

The firebox proper is defined by side sheets H -tl. attached at their lower edges to the mud ring and usually formed integrally with the crown sheet 52, An inner back. sheet I3 cooperates with the sheet Hi to form a water leg at the.

rear of the firebox through which a fire door I4 is provided. The crown: sheet I2 extends forwardly ever the combustion chamber l5 which extends into the boiler shell 5, and in this region the crown sheet is curved downwardly in spaced relation to the lower portion of the boiler shell as seen at it in Figure 3 to define the sides and bottom of the combustion. chamber. An inner throat sheet El join-ed to the mud ring and the rearward edge of the lower part 56 com letes the jacket at the throat of the firebox.

Flue sheet l8= defines the front end of the combustion chamber and receives the rear ends of the flue tubes [9 whichextend forwardly in the boiler.

The foregoing general structure is of known design, and in addition it has been common to stay the inner and outer plates or sheets defining the water walls as by means of bolts some of which are shown diagrammatically at 20. For

the sake of clarity only a few of such stays or bolts have been indicated in the drawings.

As in my prior Patents Nos. 1,894,613 and 2,023,620, I prefer to employ a series of water circulating devices in the firebox, each device interconnecting the side sheets with the crown sheet. In the present application, however, the devices for this purpose are of improved form and configuration. Each one includes an upper outlet portion 2! at least the upper part of which is preferably of substantially circular drosssection extending perpendicular to the crown sheet. The lower part of each element 2| in accordance with this invention is curved somewhat rearwardly as at 22 (see Figure l) to extend at its lower end substantially perpendicularly with respect to the mean plane of the arch. At its lower end the element 2| is joined with the inlet portion for the device consisting of a pair of branches 23 extended somewhat downwardly and laterally toward the side sheets and then approximately horizontally immediately adjacent the side sheets, as clearly seen at 24 in Figure 2. Each of these circulator devices thus in effect incorporates a generally upright outlet portion and a forked inlet portion, the branches 23 of the fork, as with the outlet portion 2|, preferably being of substantially circular cross-section.

Beginning at the rear of the firebox, the several outlet portions for the series of circulator devices progressively increase in length as is clearly shown in Figure 1, and as further appears in this view, the branches 23 are somewhat arched transversely of the firebox in a plane approximately perpendicular to the mean plane of the arch. The arch brick 25 intervene between the adjacent and parallel inlet branches 23 and are supported thereon to form a practically unbroken fire wall at a level adjacent the upper surface of the branches 23. Additional brick 25a bridge the gap between the forward firebox circulator and the throat of the firebox.

By employing circulator devices of the character described, and particularly with the inlet branches 23-43 transversely arched in a plane perpendicular to the mean plane of the brick arch, a more effective support for the brick is afforded and, in addition, the size and the shape of the brick may be the same substantially throughout the entire arch. The throat brick 25 are the only ones in this embodiment which are of a different pattern.

Furthermore, by employing outlet connections for the circulators of the type shown at 2| I am enabled more readily than in prior constructions to accommodate the circulator devices to any particular installation, this for the reason that with an outlet connection having a bend intermediate its ends, the outlet apertures in the crown sheet may be shifted somewhat to different positions longitudinally of the firebox. Various boiler appurtenances are commonly associated with the outside wrapper sheet 6 and in making the circulator installation it is necessary to arrange the outlets through the crown sheet in positions to avoid interference with such appurtenances.

In addition to the foregoing, the present invention also employs a circulator device located at least in large part in the combustion chamber l which is frequently provided in the rear end of the boilershell. This circulator preferably includes inlet branches 26 communicating with the water jacket at the sides of the combustion chamber, and an outlet portion which is upwardly forked to provide branches 21-48 lying in a longitudinal vertical plane and connected with the crown sheet in the region thereof above the combustion chamber l5.

This circulator in the combustion chamber is of special advantage for several reasons, including the fact that it provides for constant flow of water .over the crown sheet above the combustion chamber which is ordinarily the highest portion of the crown sheet and therefore the first to be exposed in the event of a drop in the water level.

While periodic inspection of the boiler equipment, and proper attention to the gauges will usually avoid an abnormal drop in the water level, from time to time, either through negligence or other causes, the crown sheet, particularly above the combustion chamber is exposed. When this occurs in an elongated area along the center of the crown sheet, the crown sheet suddenly gives way, resulting in a violent explosion. With regard to this point, it must be borne in mind that the increase in temperature resulting from exposure of the crown sheet weakens the crown stays, so that they will pull out quite readily. By employing the improved circulator in the combustion chamber damage resulting from low water level is largely eliminated since, in addition to providing a constant flow of water over the areas adjacent to the outlets, the circulator constitutes an effective brace or support for the crown sheet. This is especially true when employing a bifurcated outlet, the support being thereby distributed lengthwise along the area which is first exposed upon drop in water level.

I prefer to form all branches of this circulator in the combustion chamber of circular cross-section, since this form of construction affords the strongest bracing.

The arrangement of Figure 4 is in many respects similar to that of Figur 1 to 3, although in Figure 4 the improvements of this invention have been applied to a locomotive in which the combustion chamber 29 is somewhat shorter than in Figure 1. In Figure 4 all of the circulators employed are arranged in a single arch brick supporting series, but the front circulator device, instead of having a single outlet portion 2|, is here provided with a bifurcated outlet portion having branches 3!] and 3| lying in a vertical longitudinal plane. The forward branch 3| is connected with the crown sheet above the combustion chamber 29 and the rear branch 30 with the crown sheet adjacent the rear edge of the combustion chamber.

In this arrangement, therefore, the front circulator has its inlet branches 23 communicating with the side water legs of the firebox and its outlet branches 30 and 3| communicating with the space above the crown sheet, and as a result highly effective circulation is provided from the lower forward portions of the side water legs upwardly to the highest point of the crown sheet, i. e., the region in which it is most important to provid against exposure of the crown sheet as well as to provide additional support therefor.

Because of the longitudinally spaced points of support for, and delivery of water to, the crown sheet, provided in accordance with both forms of the invention, in the event of the water level dropping sufficiently to cause substantial overheating, the crown sheet gives way only in relatively small localized zones so that the boiler pressure is dissipated without violent explosion.

Attention is called to the fact that certain features herein disclosed are described and claimed in my copending divisional application Serial No. 399,134, filed June 21, 1941.

I claim:

1. In a locomotive boiler having a firebox and an adjoining combustion chamber, a circulator device positioned at least in large part in the combustion chamber, said device having upper and lower outlet and inlet portions forked in generally vertical planes substantially at right angles to each other, the branches of the lower fork extending in a substantially transverse plane and connected with th boiler space well below the crown sheet, and the branches of the upper fork extending in a substantially longitudinal plane and connected with the crown sheet, at least one of said last branches being connected with the crown sheet at a point disposed well forwardly in the combustion chamber.

2. In a locomotive boiler having a firebox and an adjoining combustion chamber, a circulator device positioned at least in large part in the combustion chamber, said device having upper and lower outlet and inlet portions forked in generally vertical planes substantially at right angles to each other, the branches of the lower fork being of substantially circular cross-section and extending in a substantially transverse plane for connection with the boiler space well below the crown sheet, and the branches of the upper fork being of substantially circular crosssection and extending in a substantially longitudinal plane for connection with the crown sheet, the two forked portions being interconnected toward their base ends and at least one branch of the outlet fork being connected with the crown sheet at a point disposed well forwardly in the combustion chamber.

3. In a locomotive boiler having a firebox and an adjoining combustion chamber, a series of circulator devices each having a generally transverse inlet portion connected with the side sheets of the firebox and at least one of said devices having a forked generally upright outlet portion, with the branches of the fork lying in a generally longitudinal plane and connected with the crown sheet, one branch being connected with the crown sheet at a point located well forwardly in the combustion chamber and another adjacent the rear edge of the combustion chamber.

4. In a locomotive boiler having a firebox and an adjoining combustion chamber, a circulator device positioned at least in large part in the combustion chamber, said device having upper and lower outlet and inlet portions forked in generally vertical planes substantially at right angles to each other, the branches of the lower fork extending in a substantially transverse plane in the combustion chamber and connected with the boiler space therein well below the crown sheet, and the branches of the upper fork extending in a substantially longitudinal plane and connected with the crown sheet, at least one of said last branches being connected with the crown sheet at a point disposed well forwardly in the combustion chamber, and another being connected with the crown sheet adjacent the rear edge of the combustion chamber.

5. In a locomotive boiler having a firebox and an adjoining combustion chamber, a circulator device positioned at least in large part in the combustion chamber, said device having upper and lower outlet and inlet portions forked in generally vertical planes substantially at right angles to each other, the branches of the lower fork extending in a substantially transverse plane in the firebox and connected with the side sheets well below the crown sheet, the branches of the upper fork extending in a substantially longitudinal plane and connected with the crown sheet, at least one of said last branches being connected with the crown sheet at a point disposed well forwardly in the combustion chamber, and another being connected with the crown sheet adjacent the rear edge of the combustion chamber.

6. In combination with a locomotive boiler firebox including a crown sheet and side sheets, a water steaming and circulating element in the firebox comprising an upwardly arched lower tubular-like portion extending transversely of the firebox and having ends opening through the side sheets and a plurality of spaced upper tubular portions, the top end of each of which opens separately through the crown sheet and the bottom ends of which have a common inlet that is in communication with said lower portion.

7. For a locomotive firebox having a crown sheet and side sheets, a water steaming and circulating element comprising an upwardly arched lower inlet portion adapted to extend transversely of the firebox for connection with the side sheets, and a plurality of outlet portions, the top end of each of which is adapted to be separately connected with the crown sheet, and the lower ends of which have a common inlet communicating with said inlet portion.

8. For a locomotive firebox having a crown sheet and side sheets, a water steaming and circulating element comprising an upwardly arched lower inlet portion adapted to extend transversely of the firebox for connection with the side sheets, and a plurality of outlet portions lying in a plane at right angles to the inlet portion, the top end of each of the outlet portions being adapted to be separately connected with the crown sheet, and the lower ends of which have a common inlet communicating with said inlet portion.

CHESTER A. SIEGEL. 

